Jeffreys anwser covers the business side quite well and there isn't much to add to this solid answer, but I would like to provide an answer on a more emotional level.
I can definitely understand (been in a simlar situation) that you have certain sentitments towards that very much liked and valued teammember after 3 years and that you or the team feel the need to express those while not being too intrusive.
Attending the funeral is a bit much and would be seen as intrusive by other family members or close freinds who might not even know you or the team, but a personal, handwritten condolence letter from the team to the family would be a resonable and appriciated reaction:
[enter name here] was a great team member and much valued and appreciated by me as well as many others in the team. ..
Note special qualities of the deceased, recall a memory of the deceased, remind the bereaved of their personal strengths; offer help but be specific and end with a word or phrase of sympathy for the ones who are left behind mourning.