Wwyd? P/t job 18h pw but full time 6 weeks a year

[duploinmyteaagain]

I have been out of paid employment since having my child two years ago. I have applied for a job which sounds great, lovely hours, not too far away and the right kind of role for me but for 6 weeks a year I would be required to be full time to cover for a colleague.
Would you take a job with these hours? My concern is what I will do re childcare.
I would plan to put Dc into nursery two days and with my parents the other day but what could I do for those 6 weeks? It would be too much to expect parents to have Dc 3 days a week.
I'm torn because the p/t role looks really good and I haven't found many to apply for but would these 6 weeks be a complete PITA?
I don't have further details on how the six weeks would be broken up but imagine it could be a couple of two week blocks plus odd days...

[duploinmyteaagain]

Thanks newnoo. I think extra flexi days may be an option at the nursery.
I hadn't thought of a temporary nanny service, so I'll look into that too.
I am also now considering a childminder rather than nursery as I've been led to believe they can offer more flexibility.
So many different options!?