What happens if he/she wiggles during the casting process?
Wriggling babies are not a problem, we use ‘fast set’ alginate which does what it says on the tin, and will be set before they really have time to wiggle. If possible, we like to take casts just after a nap or feed, when they are usually most calm. The feeling of alginate on skin is not unpleasant and we use a mix at body-temperature for most moulds.