They have made a sequel to Boss Baby (no connections to netflix series).

Boss Baby: Family Business
Tim (kid in the first movie) is now a dad of his own with 2 daughters (one same age as he was in first one) and baby daughter. When his brother Ted (an adult version of the boss baby) comes to visit. The two fight. Turns out Tim's baby daughter is a boss baby herself and needs their help. To stop a mad man from turning babies into bad babies. She gives them a formula that turns Tim back into a kid and Ted back into boss baby for 48 hours.

The trailer shows an actual process.

https://www.youtube.com/watch?v=kRPUhENEavI