Around age two, appetite can still look normal. That is when many families start locking the fridge.

Miller's phase 2a had a median onset of 2.08 years. Weight increased without a clear rise in calories or food interest. Phase 3 hyperphagia came later, median age 8. Waiting until hunger is obvious usually means starting after the early weight gain has already begun.

Locks reduce sneaking and gastric risk, not punishment.

Satiety is impaired here. Association materials call this food security. An unlocked kitchen is how some children eat a very large amount at night and later present on the emergency page.