When they’re a toddler, of course.
It’s a hard one to know when they transition from baby to toddler.
My view is as soon as they’re up and walking on their own, then it should be fairly obvious they’ve made the transition. N definitely coincided his walking with the toddlers need to be into everything, usually with a cheeky glance at us to check whether we were watching and/or disapproving.
But, it’s hard to call him a toddler. I still tend to refer to him as baby, even though he’s obviously not. I guess little ones will always be the baby.