Plans for Westfield North Rocks to expand will force a long-established preschool to move.
A closed meeting was held at The Hills Council on Tuesday night to decide the future of North Rocks Preschool.
Westfield wants to acquire the council-owned land on which the preschool stands.
The sale was approved, despite letters from parents, staff and a former pupil, 10, to councillors.
Details of the offer remain confidential as the council believes it would be at a competitive disadvantage in negotiations and not get a "best value for money" outcome for the wider community if details were made public.
"It's disheartening," preschool director Samantha Forster said.
"The preschool has been here for 45 years, long before Westfield. Ideally, we don't want to move. It's not just about money invested into the place. There's also been a lot of love, heart and soul put into it."
About 100 children go to the preschool each week with another 300 on the waiting list.
Mr Forster attributes the popularity to its convenient location near schools and the preschool's impressive rainforest that attracts wildlife.
"It's described as an oasis in the middle of nowhere," Ms Forster said.
"[The rainforest] was started when the preschool opened, so it's something that can't be rebuilt."
The council has proposed to move the preschool to North Rocks Park or nearby John Wearn Reserve in Carlingford, located close to another day care facility.
"The proposed locations are difficult to get into," Ms Forster said.
She called on Don Moore Reserve to be considered so the preschool could stay in the vicinity, or whether it can be "tastefully" incorporated into any Westfield expansion.
Read 10-year-old Jade Pinar's letter to councillors
Dear Council Members,
Many people including myself are upset that you might close down North Rocks Preschool. You shouldn't close the preschool down because it's apart of our community.
Lots of children including my sister and I went there and it prepares you for kindergarten.
Firstly its apart of our community and lots of people will be sad to see it gone. Why do you need more shops when you have a lot of shops next door.
Secondly a lot of children went there and it will be sad to see it be knocked down. We have a lot of preschool memories there.
The teachers at North Rocks Preschool are very caring and helpful.
The preschool is different to other preschools because it runs in school hours and prepares you for Kindergarten. I loved going there!
I hope you agree with me and many other people to not close down North Rock Preschool!
Jade Pinar (age 10)