Ok I'm not going mad but this did happen:
Went over to my stables to show Dh where I wanted my outdoor security light putting.
Whilst he was up the ladder securing it to the side of the stables I started tying up hay nets and doing waters (we have two horses and my DD pony)
When I went into DD's pony's stable and whilst doing his net I heard something 'plop' into his water bucket (large builders rubble type bucket)
I went to look and it was a mouse that must have just fallen in (we find them sometimes in the horses buckets dead in the mornings but not very often)
I shouted for Dh to come quick. I'm not a wimpy sort but I didn't want to touch it but also didn't want it to drown.
My daughters pony went over to the bucket whilst I was standing in the stable door and looked down at the mouse and then to my utter amazement he pushed some of the straw up the side of his water bucket asthough he did it all the time so some of the straw went into the water and the mouse climbed out!
I have had horses all my life (parents had them so brought up with them) and I have never seen anything like that. One animal helping another from a different species?
My Dh thinks iabu and the pony didn't 'help' the mouse out of the bucket but I saw it with my own eyes
so I know it happened.
After a lot of 'yes it did'. 'No it didn't' I tried to recreate it with my DD wind up fish which her pony promptly picked up out of the water bucket (I think he thought it was a treat I'd dropped in as she sometimes puts an apple in there for him to 'bob' to occupy him) and he bit and broke it 
but I know he did it.