Local couple that runs a Chinese restaurant

There's a couple that run a Chinese restaurant in my town. They are both from China. They have been in town for over 20 years. Over that time they've become very friendly with me and my family, ask after my kids, remember their names, tuck little extras in my take out from time to time... Just really nice people.

One time I wanted to give them a gift at Christmas so I made up a tin of home made candies.

The next time I went in they had gotten my children those red envelopes with a little money in them and good luck candies and a gift card for my husband and I.

I know there's a cultural aspect to gift giving for them, but I felt badly because I just gave them a small token of friendship and then they spent money on me and mine.

I wanted to give them something for Christmas this year as they have welcomed their first grandchild and are over the moon about it.

Is there a good way i can go about this without making them feel obligated to reciprocate?