Rice cereal in milk..what age?

Ryan
At which age did you guys start giving your baby rice cereal in there milk? My baby is very fussy from 7pm to 11pm and wants to eat every hour and someone said to give them that in there milk and it will help fill them up and that's what they did with there child and it worked. Side note I'm a ftm and my baby is 3 weeks and 1 day now.