public SIBLINGSTATUS isSibling(int lineNumber) {
		if (this.lineNumber == lineNumber)
			return SIBLINGSTATUS.ME;

		if (this.parent == null) {
			if (this.lineNumber <= lineNumber && this.lineNumber + this.childs - 1 >= lineNumber)
				return SIBLINGSTATUS.FIRST;

			return SIBLINGSTATUS.NONE;
		}

		int parentStart = this.parent.getLineNumber();
		int parentEnd = parentStart + this.parent.getChildCount() - 1;
		if (parentStart <= lineNumber && parentEnd >= lineNumber) {
			if (parentStart == this.lineNumber)
				return SIBLINGSTATUS.FIRST;
			if (parentEnd == this.lineNumber)
				return SIBLINGSTATUS.LAST;
			return SIBLINGSTATUS.MIDDLE;
		}

		return SIBLINGSTATUS.NONE;
	}