Multiple small kids are incredibly disruptive to this. Just, a continuous "happening", constant out-of-context asks and "situations". 5 different things can happen between noticing or thinking of a task and being able to do anything about it. God help you if you have to go from one room to another because that in itself requires explanations (the best case is they quietly follow you to find out whats going on).

There are long stretches of my day where functionally, I have no free working memory at all. The main way I stay barely functional is by keeping memory "in the state of the world". The way I remember I promised to fix the tap today is by placing the tool kit prominently next to the tap, etc. As a last resort I try to write things down.