Forgotten items on contact days. Whose responsible?

[Spanglyprincess1]

So dsd is lovely but forgetful.
She again left something in the car at drop off for school, her summer coat despite being reminded along with her brothers to check if she had everything.
School is a 40min drive away in diff Town. Exw moved not us.
Dp has the baby all day till 3 then is at work till late. Dsd has other coats at her mom's but heavier weight ones - she's 8.
Exw demanding dp drop of the coat which is an hour and a half journey (there an back) with bbay in the car or lost work time.
Unreasonable to ask dsd to use her other coats as she forgot it after being reminded, and it will be returned at weekend or if its important for exw to collect it herself?

It's the age they are particular forgetful but also should be the age they learn the consequences so that by the time they start secondary school, they are responsible for their things.

I was really surprised the number of year 7 who constantly forgot things these were the kids who were not bothered because mum would always come and bring things, the same mums who still woke up their 16yo every morning and ensured they left for school because otherwise the kids went back to sleep.

My kids went back and forth every weekend, there were items forgotten, a few tears a couple of times with some dramatics, but by the age of 9, they could pack their own suitcases to go on holidays and by 10yo, they could be totally trusted with the house keys. Neither ever lost them, nor their phones.