Please don’t lend it. Next week your boiler could break, your roof might leak, your own car might fail it’s MOT.
I imagine it’s not been that easy to save £5k. You’ve probably gone without things in order to do this.
You’d have no way easy of making them pay you back and it sounds like they don’t have a huge amount of spare money so even if they start paying it back, it’ll be in dribs and drabs. Then they’ll need to “just miss this month” due to kid’s birthdays, Christmas, school trips etc etc.
I lent money to a good friend a few years back and it was agreed they would pay it back over three months - May, June and July, for context.
First month, no problem, second month, no problem. Third month and they didn’t have the money, but would “pay next week”. This money never came despite repeated requests and multiple promises.
After several months of this, by now October, I needed the money to start sorting my own families Christmas (gifts, food etc) and gave them a deadline to please pay by the end of November.
It ended the friendship - they went ballistic, called me all the names under the sun, said I was taking food from their children’s mouths, would be ruining their Christmas as they’d not be able to get presents for their children and bad-mouthed me to any friends and acquaintances.
My name was mud thereafter - the money never came; I struggled with Christmas yet their kids had an inordinate amount of presents - new bikes, an iPad, clothes etc. and they went on a New Year’s holiday!!
Like a previous poster said, you’ll end up losing the money AND the friendship. Only the friendship is at risk if you say “no”.
Interesting that they’ve presumably already asked family who’ve declined (most people would ask family first before asking friends surely?)