It's the first time anyone but me has put her to bed without tears and drama for 21 months!
Self inflicted, because I always put her to bed in the early months. By the time I'd stopped being so PFB she didn't want anyone else at bedtime.
We go out occasionally, but grandparents (our amazing babysitters!) always have a struggle at bedtime so I tend to put her to bed then go out late. DP tries to put her to bed every week or so but usually it ends in her screaming for me 
Tonight she went up for her bath with him without any protest, and I've just heard him say goodnight and walk out of her room without so much as a whimper from her.
I'm so relieved! It's so very true what you all say... This too has passed!