Can condo association change bylaws to a 55+ community?

Can owners/buyers be specifically limited to those over 55 years of age and without children? We have a small (eight unit) condo complex (two buildings) and they were not built for children. One family had two small children and two dogs and two vehicles in a two-bedroom, one car garage condo. The immediate neighbors were able to hear running children and barking dogs constantly. This family is now moving and have sold their condo to a widow over the age of 60. I would like to now adjust our condo association bylaws/rules to include no sale to anyone under the age of 55 or with children living at home. Is this legal and possible? Also, do condo association bylaws/rules need to drawn up by an attorney or can it be done by the owners of the condos?

Making amendments to condo association bylaws