Interesting discussion on the possible baby dedication - although, as has been said, they may keep any such decision a purely private matter.
As Abbey said, the age for Christian Baptism varies a lot between the different churches. Traditionally, it has been performed as soon as possible - and this is done in the older churches of both East and West, and is also done by several of the Reformed churches, including Lutheran, Anglican, and most Methodist and Presbyterian. The Baptists were the main Reformed group to practise only Believers' Baptism (usually of adolescents, or older professing Christians), and this is also practised by Restoration churches, such as the Churches of Christ, and the Latter Day Saints.
In my church, Baptism is normally practised for babies, and is followed several years later by Confirmation. (If you're not familiar with Confirmation, it's decscribed here;
The Sacrament of Confirmation in the Catholic Church
I was confirmed at about eight (which is probably also about the earliest that the churches practising Believers' Baptism would also administer their Sacrament), but in both cases, it's also often received later, e.g, as teenagers)
Interestingly, both traditions appeared in recent songs by the leading Country ladies. Carrie's song, SITW, obviously refers to a later, Believers' Baptism, where she 'follows the preacher man down to the river' - while Miranda's song, BMB, refers to infant Baptism, with the line 'but all has been forgiven on the day the water Christened.'
It's my understanding that Carrie worships at an Affirming Baptist church - so she is likely to leave Isaiah Mike's faith decision until he's older. If you're not familiar with the practice of dedicating a baby, there's an explanation here:
Explore the Practice of Baby Dedication
