Babysitter/Nanny for wedding

We are needing a babysitter/nanny for our 2 girls on the 6th December as we have a wedding. The wedding is in Brighton which the girls are going to, but for the reception we were needing someone to look after them at the hotel (in Brighton). As this is new to us and them, we were wanting to make it possibly a weekly or fornightly thing leading up to the wedding so the girls and us are comfortable with someone new. We are located in Mernda (Possibly continuing after the wedding into next year)