This is your first full season of international sevens. What has been the biggest eye-opener?
Going from a non-professional to a professional sport and everything that comes with that. Getting paid is probably the biggest one, getting to travel the world all expenses paid.
You were a touch player, so how have you been able to transition to take the hits?
A lot of skills transfer over from touch, but the contact area was the hardest thing to pick up.
But I do have two big brothers to help out with that and my whole life I've always been the harder toucher in touch. I guess it's more about attitude and learning the technique as I go.
You're a mum as well to Tatum-Lee and Rema-Rae, so how do you juggle the kids, travelling the world and playing professional sport?
One word: family. They help out a lot, especially my partner Tama. His family, too. His brother and sister are my kids' adopted parents because they're always with them.
Without them, none of this would be possible. So, yeah, just the family support.
The kids are 2 and 3. Are they too little to get what's going on, or do they think it's cool?
When they see me on TV, they're like "Mummy, No 4!". That's really cute, but Tatum, she's always like "Mummy are you going training again?" and it's like, "Yes, darling".
Niall is quite an unusual name for a girl. Where did that come from?
Well, I have two older brothers and when my mum found out she was pregnant with twins, she said if one of them was a girl she would name her after her mum Denise. So that was my older sister Denise.
Then another girl came out but my dad had a name for a boy which was Niall.
My mum didn't know it was a boy's name so my dad sneakily put that one in there.
Apparently it's Irish for John, my dad's name. My oldest brother's name is John-Afa, so he's got two Johns in there and likes to think he's clever.
So you have two older brothers and a twin sister.
Yep. And my sister is 10 minutes older and I get reminded of it all the time.
It would be amazing to have two members of the family at the Olympics. What would it mean to your family to have the Williams name on two black jerseys in Rio?
Even with me playing touch and all of Sonny's achievements, they're already proud. But the Olympics are the pinnacle of sport so, if we both made it, the family would be ... I guess words can't describe the feelings they would have, but proud comes to mind straight away.
You put up a cheeky Instagram post about flight seating arrangements recently. Were you taking the mickey out of your brother or making a subtle point?
[Laughs] I was taking the mickey out of my brother. It's quite funny because a lot of people don't realise, from his post apparently, we now get 10 upgrades per team and our ones are drawn out of the hat.
But that flight I obviously missed out. So I was pretty much taking the piss out of him.
Your brother is very well known and people have cracks at him in the media and on social media. How hard is it to bite your tongue?
We're quite a proud, strong, close-knit family and I guess, over time, it's become easier because he's been doing it professionally since he was 18 years old.
So I've learned over the years with a bit of help from my brother. He's like, "Don't worry, sis, everyone who matters, their opinion matters, no one else does".
If you weren't doing this, travelling the world and being a professional sevens player, what would you being doing?
Being a mum, and then something to do with sport.