The move is part of a one-year feasibility study funded by Sure Start Sunderland to assess local demand for weekend childcare.
The private day nursery is located at the edge of Sunderland city centre.
Since November, the nursery has been opening from 8am to 6pm on Saturdays, and 9.30am to 4.30pm on Sundays, to fit around the schedules of its children's parents, many of whom work in local shops, hairdressers or banks.
Gillian Williams, early years director at Tavistock House Day Nursery, said, 'We have had really positive feedback from parents who say it can be a nightmare to find care at the weekend, while they're working, and that they have found it so much easier knowing the care is there.'
Weekend care is available both for parents of children who attend the nursery during the week, and also parents who may need ad-hoc childcare at the weekend, and can book on an hourly or daily basis. Sure Start Sunderland is covering the nursery's running costs for weekend opening.
Ms Williams said, 'We have had 15 to 20 children use the weekend opening so far, and we can expand to our full capacity of 71 children aged three months to 11 years old if there is sufficient demand.'
Ms Williams added that nursery staff members have been happy with the extended opening times, 'Staff choose whether or not they work at weekends.
Those who do are happy as they get an increased rate of pay and can work one day less during the week. We are not adding weekend working to anyone's contract.
'As the study is in its early stages, we will assess the best way to approach staff provision at weekends and develop procedures accordingly.'