diff --git a/src/_igraph/graphobject.c b/src/_igraph/graphobject.c
index 894e35d26..49e025003 100644
--- a/src/_igraph/graphobject.c
+++ b/src/_igraph/graphobject.c
@@ -15854,7 +15854,8 @@ struct PyMethodDef igraphmodule_Graph_methods[] = {
    "@param vertices: a single vertex ID or a list of vertex IDs, or\n"
    "  C{None} meaning all the vertices in the graph.\n"
    "@param order: the order of the neighborhood, i.e. the maximum number of\n"
-   "  steps to take from the seed vertex.\n"
+   "  steps to take from the seed vertex. Negative values are interpreted as\n"
+   "  an infinite order, i.e. no limit on the number of steps.\n"
    "@param mode: specifies how to take into account the direction of\n"
    "  the edges if a directed graph is analyzed. C{\"out\"} means that\n"
    "  only the outgoing edges are followed, so all vertices reachable\n"
@@ -15882,7 +15883,8 @@ struct PyMethodDef igraphmodule_Graph_methods[] = {
    "@param vertices: a single vertex ID or a list of vertex IDs, or\n"
    "  C{None} meaning all the vertices in the graph.\n"
    "@param order: the order of the neighborhood, i.e. the maximum number of\n"
-   "  steps to take from the seed vertex.\n"
+   "  steps to take from the seed vertex. Negative values are interpreted as\n"
+   "  an infinite order, i.e. no limit on the number of steps.\n"
    "@param mode: specifies how to take into account the direction of\n"
    "  the edges if a directed graph is analyzed. C{\"out\"} means that\n"
    "  only the outgoing edges are followed, so all vertices reachable\n"
diff --git a/vendor/source/igraph b/vendor/source/igraph
index 635b432ef..662abbdfa 160000
--- a/vendor/source/igraph
+++ b/vendor/source/igraph
@@ -1 +1 @@
-Subproject commit 635b432eff0a89580ac9bb98068d2fbc8ef374f2
+Subproject commit 662abbdfa467a6436bad650c31a8360787d75379