Speech is highly individual
All children learn to talk in the same order. First they use single words, then phrases and finally whole sentences. But apart from this, it’s very individual how children learn and master speech. They each have their own personal timeline. It may be fast or it may be slow. Sometimes nothing seems to happen at all, then suddenly there's a giant leap forwards.
So don’t make comparisons. This is a good rule to remember for lots of things.
Find out what happens next by looking forward in the timeline.