Literally at our wits end with this.
Have a nearly 4yo and a 8yo....8yo has ADHD so its more like having two preschoolers at bedtime to be honest.
Since youngest has not had a stairgate on her room due to climbing over it, and
has been increasingly hard to settle, its been hellish as she runs into other DD's room and older DD just encourages it and gets tempted to play with her.
Short of us sitting outside their rooms and never getting an evening, or letting them just get on with it and crash out at 10pm, I don't know what we can do.Both take too long to settle to stagger bedtimes, plus if one knew the other was downstairs they would just keep coming down anyway.
Eldest is constantly up late whatever time she wakes up in the morning.
If she doesn't get enough sleep her behaviours and emotions are all over the place 🤦♀️