We prove the existence of continuous boundary extensions (Cannon-Thurston
maps) for the inclusion of a vertex space into a tree of (strongly) relatively
hyperbolic spaces satisfying the qi-embedded condition. This implies the same
result for inclusion of vertex (or edge) subgroups in finite graphs of
(strongly) relatively hyperbolic groups. This generalises a result of Bowditch
for punctured surfaces in 3 manifolds and a result of Mitra for trees of
hyperbolic metric spaces.Comment: 27pgs No figs, v3: final version, incorporating referee's comments,
to appear in Geometriae Dedicat