I think if she is consistently doing this then she may need a routine tweak, which may even mean letting her sleep longer for 1 nap but capping the other but if this is unusual I would def leave, tehee are so many reasons they need random periods of more sleep, GS, illness, teething etc. I also think it depends on your LO's age and temperament. If like me and prob Kara too
then waking LO from a nap just makes for a cranky baby all day long...and when LO is taking a longer nap there is reason for it. BUT if your LO is a sleepy baby and the long naps are ruining your nights etc then you may need to look at adjusting your day and your LO's nap lengths....
Hope that makes sense