Acts 2:1-4 (ESV):
When the day of Pentecost arrived, they were all together in one place. 2 And suddenly there came from heaven a sound like a mighty rushing wind, and it filled the entire house where they were sitting. 3 And divided tongues as of fire appeared to them and rested on each one of them. 4 And they were all filled with the Holy Spirit and began to speak in other tongues as the Spirit gave them utterance.
Acts 4:31 (ESV):
And when they had prayed, the place in which they were gathered together was shaken, and they were all filled with the Holy Spirit and continued to speak the word of God with boldness.
Were there any believers present at both events?
More generally: can Christians be filled with the Holy Spirit more than once?
Note: if the set theory terminology used in the title is a bit confusing, please see https://en.wikipedia.org/wiki/Intersection_(set_theory)