I've always thought of it as "Seresponda, seresponda", something like this:

Seresponda, seresponda, seresponda, ret-set-set*,
Seresponda, seresponda, seresponda, ret-set-set*,
Adóreo, ah do re boom-day oh,
Adóré boom-day ret-set-set,
Hossay possay oh!

We always sang it (in my family as a kid; it was a roadtrip song, in the late fifties and sixties) as a medley with

Qui que money-money-money-money dusty
Qui que quo, qui que quum
Qui que money-money-money-money dusty
Qui que quo, qui que quum
O Nicodemo, O jolly-olly-umbo!
O Nicodemo, O jolly-olly-oompa-oompa-oompa!

Shades of Macnamara's Band and Bill Grogan's goat! ;-)

Liland

PS I'll try to whip up a MIDI in the next few days of the melody line as I recall it, but in the meantime try that spelling... And my best wishes for the little girl.