Take him with you on rides!

1. Get some aero bars on your roadie.
2. Loosen your stem and rotate the entire bar assembly until aero bars are vertical, re-tighten.
3. Get one of those baby chest carriers.

Ride upright, with baby in chest carrier, hands up high on the aero bars as far away from brakes and shifters as possible, elbows bent pulling you in close to hold your baby securely (aka squishing the **** out of him) between you and the bars. If you get it positioned just right, the front of levers can act like elbow rests, just don't lean on them too hard.

I kid you not, I saw a woman doing this on the MUP a few weeks ago.