Chrissy Teigen is struggling to find a name for her unborn baby.

The 'Sports Illustrated' model - who is expecting her second child with her husband John Legend - admits she isn't sure what moniker to pick for her impending arrival.

Captioning a picture of a number of unisex baby names, she wrote on Twitter: ''Jesus Christ my baby will have no name (sic)''

A source had previously revealed that John and Chrissy are ''so excited'' that their daughter Luna, 20 months, is going to be a big sister.

They said: ''They have been planning for this for a long time. Chrissy is really excited to finally share the news. They are so excited to make Luna a big sister. They think Luna will do a great job with the baby and they're really happy to be expanding their family.''

Chrissy previously admitted she would love to be ''pregnant for the rest of her life''.

She gushed: ''I feel good, I feel good, we're still trying ... I'm going for I mean hopefully in the next few years because for me I really want to just knock 'em out. That's my dream, I want to just be pregnant kind of for the rest of my life. Not for the rest of my life, but the rest of my fertile life. So we'll see ...

''I probably think about it more than anybody. I cannot wait to have the biggest family. Everybody is curious. They're like, 'When are you going to do it? When are you going to do it? When's the process going to start?' It's so fun absorbing baby Luna right now. I think I'm enjoying my time absorbing and seeing everything - all her new little steps and new moments - and being there for them ... Every day it's something new with her. More than anything, I love seeing her little palette. She will eat anything and everything. I just think it's so fascinating. You give her the whisk and she knows exactly what to do the second you teach her. It's really cute.''