Bepanthan is good.
The yellow one mentioned by DTC could be Kamillosan, I think thats how you spell it, its thick, yellow and made with camomile.
Personally i would go with the egg white, old midwife recomended it to me many years ago , and it worked wonders on mine.
Whip up an egg white til its stiff, dont worry about your pastry brush ( pmsl with that ) just dab it on with some cotton wool, let it dry before you put nappy back on, it forms a skin like coating and stops the wee or the other hurting already sore skin.
Hope little nobs is better soon, its rotten when they are poorly. X