Hola!
As far as I know you are entitled to use the MAD lounges if you fly on Oneworld flights and entitled to bring in a guest, do not know how family policy works there.
More info at:
http://www.iberia.com/OneToOne/v3/pr...ANONYMOUS=true
That is: Iberia.com, Information, At the airport, VIP lounges.
I do not know about LIS.
Enjoy your flight and stay!
Salut!
Roger