A mum-of-four is answering all of the uncomfortable questions 'tweens' need answers to.

When Rosie hit puberty, she had so many questions she wanted answered. So, the now mum-of-four talked to girls from all over the world to give them the answers she wished she’d known.

Kimberly asks: “One breast is bigger than the other. Is this normal?”

This is really common and it’s perfectly normal. You may find your nipples or areolas look different from each other as well. During puberty, you may find your breasts grow at different rates and that’s normal too. They usually even out when you get older, but it’s okay if they don’t. A lot of women have different-sized breasts. If you are really worried about the size difference, you can talk to your doctor about it.

Hannah asks: “What is discharge?”

Vaginal discharge or secretions is fluid or mucus that leaks out of a girl’s vagina. It usually begins to occur a few months before first getting your period, caused by the changes in hormones. Discharge can be thin and sticky or thick and gooey. It is usually clear in colour and helps with fighting bacteria and keeping the vagina healthy.

Josie asks: “Why do you get cramps before and during your period?”

Cramps are caused by chemicals called prostaglandins; these chemicals cause the uterus to contract and help push the lining out through the vagina during your period.

Xiu Chi asks: “How long can you wear a tampon for?”

Tampons should be changed every 4-6 hours and not left in longer than 8. Overnight it is recommended to wear a pad, wearing a tampon for longer than eight hours can be dangerous.

Sally asks: “How often should I change my pad?”

Changing your pad really depends on the flow of your period. If your period is light you may be able to leave your pad on for a few hours. If your period is heavy, you may find you need to change your pad more often. You should aim to change your pad every 4 hours though, as bacteria can start to grow in the blood and cause odour and infection.

Gillian asks: “Why haven’t I gotten my period yet? All my friends have?”

The first thing you need to know is that everyone is different and we all develop at different rates. You may feel embarrassed that your friends have all gotten their periods and you haven’t, but it’s not a race and your period will start when your body is ready.

Thank you to these gorgeous girls for being my focus group today! Talking all things girly ???? Book launch is fast approaching! Exciting things to come ????????????????????????

A post shared by R O S I E L U I K (@rosie_luik) on Apr 3, 2017 at 7:13pm PDT

Lisa asks: “What is the difference between pimples and acne?”

There is a difference between pimples and acne. Getting the occasional pimple during puberty is normal, but if these pimples become excessive and spread across your face then it’s classed as acne. Acne can last a lot longer than a pimple and can become persistent. You may need to visit your doctor and get medication if you suffer from acne.

Hannah asks: “Can I go swimming when I have my period?”

You can absolutely go swimming when you have your period; you just need to use a tampon. If you use a pad while you’re in the water, it won’t absorb any leakage and will turn soggy. If you are self-conscious about using a tampon, you can always wear board shorts or dark-coloured swimwear.

Melanie asks: “My period is irregular. Is something wrong?”.

When you are just starting your period, this is very common. Your body is trying to get used to all the changes happening and can cause your period to be light or irregular. Stress can also be a factor, so try not to worry about it at all, because it’s completely normal. If you are really concerned, you can always talk to a doctor about what’s going on.

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Teagan asks: “Why don’t I have pubic hair yet?”

Some girls will grow pubic hair early and some, much later. The best thing to do is not worry about it. You will grow pubic hair when your body is ready to. You might find your underarm hair grows first, and that is completely normal.

Whitney asks: “Why are there so many different types of pads and tampons?”

Tampons and pads will come in a range of different sizes; this is to suit what type of “flow” you are having. The first few days of your period are usually regular so a regular tampon or a regular pad can be used. During the third to fourth day your flow is usually quite heavy and you can choose to use a tampon or pad that is more absorbent, suitable for a heavy flow. During the last few days of your period, you will find it’s quite light and you may choose to use a low-flow tampon or panty liner instead of a pad. It depends on you and your body as well. If you find your entire period is light or your entire period is heavy, it’s okay and you can choose to use the products that are right for you.

Jade asks: “What do I do with my used tampon or pad?”

You will find that all public toilets are equipped with sanitary bins, so when you are out and about it’s easy to dispose of your tampon and pad. The bin sits next to the toilet and is emptied regularly. Never flush a pad or tampon down the toilet. If I am at home, I always wrap my used tampon or pad up in toilet paper and place it in the bin.

Michaela asks: “Does getting my period mean I can carry a baby?"

Getting your period is your body’s way of telling you that you can now reproduce. The eggs from your ovaries release every month and this means that you can get pregnant and have a baby. Although there are a lot of other factors that need to be taken into consideration when preparing for a baby, it essentially means your body can physically carry a baby.

Kylie asks: “What should I do if I get my period at school?”

Firstly, don’t stress out; it’s all okay, and plenty of people have been through this experience. Keeping a period kit in your school bag is always a great idea. Fill a pencil case with a pad, tampon and spare underwear and keep it tucked away in your school bag. Then, if your period does come you’re prepared. If you don’t have any supplies on you, the school office will and it’s okay to go and ask for some help or supplies. If you have leaked in your underwear or on your uniform, try not to panic. The office should have a spare uniform you could borrow or it might be one of those times you need to call your mum, aunty, sister or even your dad and ask them for help! Don’t be embarrassed. I guarantee they have been through it all before too.

Rachel asks “I feel sad a lot. Is this normal?”

Feeling sad is normal, mostly because all of the hormones in your body are going crazy. However, there is something called depression and that can affect your eating and sleeping abilities, how you act and your everyday life. Depression goes deeper than just feeling sad. If you think you are overly sad, having trouble sleeping and it’s happening most days, you should talk to a parent or guardian about it all. There are so many things available to help you feel like yourself again.

Rebecca asks: “I feel hungry all the time. Is this normal?”

During puberty, your body does a lot of growing and, in order for it to keep up, it requires fuel; that fuel is food. Just make sure you are making good food choices and giving your body the right kind of nutrients to keep it strong and healthy.

Peta asks: “I feel like I have no one to talk to about puberty, I’m so embarrassed?”

Puberty can be an embarrassment and that’s why I wanted to create this book – so you know you aren’t alone and what you are going through is normal. Sometimes you might have to be brave and take the first step in talking to someone. You will be surprised how easy it is to ask questions and once you start you won’t want to stop. Ask as many questions and start as many conversations with your family or doctor as you can. Remember, EVERYONE goes through puberty.

Darcey asks: "When should I buy a bra?”

Buying a bra can be a daunting task and it’s completely up to you and what you feel comfortable with. A sports bra is a great place to start – it can give you support and provide comfort while your breasts are growing and developing. If you are self-conscious about your growing breasts, a sports bra can really help with gaining your confidence back.

Lucy asks: “Why does my body have to change so much?”

If you think about it, changing from a girl into a woman is quite a huge step and requires a lot of changes. Your body is such a wonderful and powerful thing and it’s actually amazing when you sit back and look at what is accomplished during puberty. Essentially your body is changing to become ready to carry a baby both physically and emotionally. In order to be prepared, your body needs to change.

Laura asks: “I have a bump under my nipple. Is it something to worry about?”

This is nothing to worry about and is your body getting ready to start growing your breasts. When your breasts start growing, they start as little buds under your nipples. They can be sore too, but that just means they are growing. It might help to buy a sports bra to help make you more comfortable. Ask your mum or Doctor if it continues to worry you just to make sure and for your own peace of mind.

Tiffany asks: “How much do you bleed when you get your period?”

This will depend on what is normal for your body; usually a girl will lose between two and six tablespoons of blood each period. It’s hard to tell though, and sometimes you may lose more and sometimes less. If you are concerned, talk to your parents or your doctor.

Jessica asks: “I feel so self-conscious all the time and I hate it?”

Puberty is a time in your life where you become aware of your body and social image. It is important to remember you are you and nobody will ever be the same as you. Try not to compare yourself to others as everyone is different. It’s okay to feel self-conscious but just know that everyone feels this way at some point and doing things that make you feel happy is a great way to get your confidence up.

Casey asks: “Can you use a tampon for discharge?”

It is not recommended that you use a tampon for discharge as a tampon is used to soak up a flow of liquid. Discharge is normally a small amount and a panty liner is all you should need.

Johanna asks: “What is PMS?”. PMS is an abbreviation for premenstrual syndrome?”

It can occur in some girls, usually the week before they get their period. You may find your breasts tender, your back aches, you have cramps, your skin breaks out and you have more than normal mood swings. All of these are a sign of PMS and are completely normal.

Christine asks: “What is TSS? And what happens if a tampon string breaks?”

TSS stands for Toxic Shock Syndrome, an infection caused by bacteria in the vagina. This can occur if you leave your tampon in for too long, so remember to change it regularly and try not to sleep with a tampon in. If a tampon string breaks (which is not likely) you can easily remove the tampon by using your fingers to pull it out. If you still can’t remove the tampon, just make sure you see your doctor or go to the emergency room on the same day to avoid infection.

This is an extract from Help! I'm a Tweenager, written by Rosie Luik, available here. Rosie is an Australian model, author and influencer. She's also a mum-of-four and an altruistic surrogate to twins. You can see more from Rosie on her website and Instagram.