'Hello',a campaign highlighting the importance of communication in children run by the Communication Trust, has some good free resources:
Talking Point also has resources, a nice tracker for what your child should be doing at various ages as well as tips on how as a parent you can support their development:
Mabel turned 6 months old at the weekend...
She is now sitting up on her own pretty confidently, grabs everything she can get her little hands on and does a reverse worm action across the room on her back (may be something to do with the fact I don't ever remember to do tummy time. No not because I don't want to encourage crawling, honestly).
She loves being tickled, likes a good fright and continues to laugh in the face of daytime sleeping (despite not coping well with being tired).
We have also just spotted that her first tooth has come through on the bottom!
Our little munchkin has been out in the world a whole half a year...where on earth has that time gone?