Someone just told me this one:

 If your previous child says mama first, your next child will be a girl. Dada first, a boy.

My dd said dada first, so true for me.

All my boys' first word was mama, so wrong til this time!!

DD1&2 said dada first and DD3 said mama--maybe it is the opposite for me?!?

Both my boy's said Dada first however I don't think this is a very reliable one (as we all know OWT's tales are anyway haha) as majority of kids say Dada first because "Da" is generally an easier sound for a baby to make than "Ma" so therefore its usually earlier.

"Six to 12 months: babble starts with the easiest consonants -- b, d and n."  Source: Professor Carol Stoel

all of my girls said dada first but lately all DD#3 says is MUM MUM for everything she refuses to say dad if she wants food its mum anything its mum im kinda getting sick of the word mum thats ALL i hear every 2 seconds from all of them lol

If this was true, I would have 3 boys and 2 girls, lol!