Teddy Talk: Creating, Collecting, Connecting

Hi
I am new to this forum and have just made my first jointed teddy bear.  He looks really good until you get to his head which is flopping forward.  Can anyone please give me some help on how I can fix this.  He's a 24 inch bear and I only used a 20mm joint for his head.  Would a bigger one cure this problem, or have I gone wrong with the sewing part.

if you can please help, I'd be really happy as this is for my first granddaughter.

Thanks