Liam Payne certainly has his hands full with his baby son Bear. The One Direction star has gushed over his bundle of joy but admits the tot is a "chubster" having grown quickly in the four months since he was born.

Payne, 23, and his girlfriend Cheryl Tweedy welcomed their first child together in March, little more than a year after they began dating. The couple have only shared one photo of their baby boy since his birth but Payne has posted an update on the tot's development, revealing his surprise at how much he has changed in a short space of time.

In an interview with People, Payne said: "He's just big in general – he's humongous. I'm going to get a sore back. He's a big boy! He's healthy, he's strong, he likes his bouncer. I thought he looked like me, but then I saw a picture my mum sent me of myself when I was a baby and I was like, 'Woah', I was a chubster baby."

Payne has been busy promoting his solo music, including new singles Strip That Down and Get Low, meaning he has spent several weeks away from his newborn while travelling overseas.

However, the real work is about to begin as the pop star reveals Bear is on the verge of teething, stating: "I'm just going home towards the start of what could be the terrible teething."

Although Bear is still just a few months old, Payne recently revealed he and Cheryl have discussed how strict they will be in enforcing a good work ethic on their son despite their own fame and combined fortune of an estimated £70m. Payne told French radio station Just Music: "We are very lucky and we will raise him to know we've worked hard to have these nice things."

The musician added: "I discover him every day and I see his eyes brighten when I talk to him. He always looks at me with great attention and he often tries to imitate me by moving his mouth. I'm happy to be a dad, it's an incredible thing. I give my son as much love as I have received from my parents."

My close friends and family know there are very few times when I'm left speechless... wow! I'm incredibly happy to welcome our new baby boy into the world, it's a moment that I will never forget for the rest of my life and my favourite memory I have so far. I'm completely in awe of his incredible mother and how she has been the whole way through this, she's really made my dreams come true. We haven't named him yet but he's already capturing hearts including mine. I feel very blessed. Happy Mother's Day everyone!

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