Family tree node connector doesn't have transition.

[tandrast]

Need to add:

transition: all 0.5s;
-webkit-transition: all 0.5s;
-moz-transition: all 0.5s;

To src/calc2/components/raTreeFamilyTree.scss:

/*Connector styles on hover*/
.tree li div.node.active + ul li::after,
.tree li div.node.active + ul li::before,
.tree li div.node.active + ul::before,
.tree li div.node.active + ul ul::before {
	border-color: #5C5C5C;
}

Sidenote: comment says styles on hover, however the selector is not for hover.