Background
Facilitating adult sibling involvement for individuals with pervasive support needs is important. This study explores the attitudes of healthcare professionals in this process.

Method
The attitudes of healthcare professionals (n = 60) in the Netherlands were explored through an online, self-developed survey with open and closed-ended questions.

Results
Around 40% of the participants reported (partly) lacking knowledge about sibling preferences and 23% (partly) lacking practical opportunities for involving siblings. The majority (partly) perceived the involvement of siblings as an enjoyable part of their work (82%), rated their knowledge and skills positively (87%), and regarded sibling involvement as such importance that they would be willing to exert considerable effort to contribute to it (61%). Not all participants perceived it as their job to collaborate with siblings.

Conclusions
There is a need to increase healthcare professionals' knowledge about adult sibling preferences and structurally embed sibling involvement within care practices.