I am a lifelong Baptist feeling drawn to the Catholic Church. (See other posts). When I was about 9 years old I accepted Jesus as my saviour and was baptised. When I got to college I drifted away from the Lord and lived in sin for a long time. 12 years ago at the age of 32 I rededicated my life to God and think that I may have been truly saved at that time.

Since Catholics believe that baptism is required for salvation, would the Church consider my baptism as a 9 year old valid?

If you were baptized in the name of the Father, Son and Holy Spirit and water was used, it is most likely valid!!!

and since you were baptist at the time , then it is almost always accepted ... i also was 9 when i was baptized in the baptist church...i just needed to have the church in which i was baptized confirm that the baptism took place ...i was glad that particular church was still in business ... though i would have been just as happy being baptized in the Catholic Church

could I be baptised in the Catholic church just to be sure

not if you were baptized and can have it confirmed... remember what the bible says... ONE baptism... there are conditional baptisms though

You would have to talk that over with the people in the parish where you join, but if it's certain that you were baptized with water in the name of the Father and of the Son and of the Holy Spirit, then there's no need for it. If there's some doubt, it can be done conditionally: "If you are not already baptized, I baptize you in the name of the Father and of the Son and of the Holy Spirit."