Convert a String to AnyVal based on some other specification in Scala

Question

I have a service which will return me a XML file as data, and there is also a schema of the data.

<RECORD>
    <PROP_VAL NAME="name"><VAL>Tim</VAL></PROP_VAL>
    <PROP_VAL NAME="age"><VAL>13</VAL></PROP_VAL>
</RECORD>

There is specification of each property what type of data it would contain, and hence I can "safely" convert age to Int. Now, what I am looking for is a small architecture which can help me to convert a String value based on the specification.

trait PropertyValue(name: String, value: String) {
    // this is a PROP_VAL I got from the XML file. And now I have a list of these objects of type PropertyValue.
    def v: T
}

The question is how do I design and implement a type hierarchy to extend from PropertyValue when I do PropertyValue("age", "13) I got something like IntPropVal.

class IntPropertyValue extends PropertyValue {
}
object PropertyValue {
    def apply(name: String, value: Value): PropertyValue // should return the concrete type
}

Several techniques that I can think of are Abstract type member, implicit convert? Am I on the right direction?