well, yes and no, Swedes.
I risk giving ammo to the 'she's a freak' camp by acknowledging a potential link with the child's developing sexuality (NOTE: CHILD's) but I also don't wish to be one of those who demonize the idea that children do develop a sexuality through childhood.
As far I can work out this is an exceptionally complex and disputed area, but it doesn't, as far as I can see, arrive fully-formed. It is linked (at the very least) to other needs and desires which we have from birth.
So, to return to Swede's analogy while shifting its emphasis slightly, I think if a child were asking repeatedly to be allowed to wear a nappy (as I assume the b/f 6yr old was doing) I would be very wary of forcing him/her to repress that urge/desire.
This is not to say that the child (not necessarily this child, but a child of six) is experiencing the desire to shit in a nappy or suck a breast as a sexual one, but that these forms of infantile desire and how they are dealt with may impact the child's developing sexuality.
And all this is a very turgid way of saying I'd go with the flow in these matters, our responses to which our children watch very carefully.