Timotheus
Paul and Silas were later joined by Timothy on their missionary journey.
They met up in Athens.
1st Missionary Journey - Barnabas. 2nd Missionary Journey - Silas. 3rd Missionary Journey - mostly alone, but assisted at various times by Luke, Timothy or Titus.
In the book of Acts it is said Paul went on his third missionary journey along with his companion who were his co workers they were young men called Silas and Barnabas.
On Barnabas's second missionary journey, he took John Mark and sailed to Cyprus, which was Barnabas's home island. They aimed to revisit the churches they had established during their previous missionary work. However, their journey later diverged as Paul chose Silas for his own missionary efforts, leading to separate paths for Barnabas and Paul.
In the book of Acts it is said Paul went on his third missionary journey along with his companion who were his co workers they were young men called Silas and Barnabas.
It depends upon the journeys. the short answer is that over all the journeys Paul was accompanied by Peter, Barnabas, Timothy, Silas, John Mark (author of the Gospel of Mark) and Luke amongst others.
I believe the scripture says they were in Philippi, the chief city in Macedonia . Acts 16:12
Silas was not with Paul in Rome during his imprisonment; instead, he was last mentioned in the Book of Acts as accompanying Paul on his second missionary journey. By the time of Paul's letters written from Rome, such as those to the Philippians or the Colossians, Silas is not mentioned, indicating he was likely elsewhere. Paul often worked with various companions, and it is believed that he may have been alone or with different associates during his time in Rome.
The woman you have in mind is probably Lydia, a "seller of purple from the city of Thyatira" (Acts 16:14). She and her household were baptized in the town of Philippi on Paul's second missionary journey, while he was accompanied by Silas. (You have to look back to Acts 15:40to see that Silas was among Paul's company at the time.)
Missionary
According to the Acts 15:39-40, Silas was Paul's second companion in his missionary trips.