public int getFrom(int i) {
        return childTrees.get(i).getFrom();
    }
Returns the character index where this {@link SpanNode} starts (inclusive), i.e.&nbsp;the smallest {@link com.yahoo.document.annotation.SpanNode#getFrom()} of all children in subtree i.

@param i the index of the subtree to use
@return the lowest getFrom() of all children in subtree i, or -1 if this SpanList has no children in subtree i.
@throws IndexOutOfBoundsException if this AlternateSpanList has no subtree i
document/src/main/java/com/yahoo/document/annotation/AlternateSpanList.java