FUNCTION [dbo].[AllSurnames]
(
	@Id int
)
RETURNS varchar(200)
AS
BEGIN
	DECLARE @Names VARCHAR(8000)  
	SELECT @Names = COALESCE(@Names + '/ ', '') + Surname FROM T_PEOPLE WHERE (r_id_family = @Id) GROUP BY Surname

return @names

END

SELECT  ID, dbo.AllSurnames(ID) AS Surname
FROM dbo.T_FAMILY

select
	a.id,
	STUFF(b.AllSurnames,1,1,'') as AllSurnames
from
	(select distinct ID from dbo.T_FAMILY) as a
	cross apply
	( select '/'+surname from dbo.T_PEOPLE b
	where b.id = a.id
	for xml path('')
	) b(AllSurnames);