#include <bits/stdc++.h>
using namespace std;
const int OO = 1e9;
const double EPS = 1e-9;
template <class T>
void _db(const char* dbStr, T e) {
  cout << dbStr << " = " << e << endl;
}
template <class T, class... L>
void _db(const char* dbStr, T e, L... r) {
  while (*dbStr != ',') cout << *dbStr++;
  cout << " = " << e << ',';
  _db(dbStr + 1, r...);
}
template <class S, class T>
ostream& operator<<(ostream& o, const map<S, T>& v) {
  o << "[";
  int i = 0;
  for (const pair<S, T>& pr : v)
    o << (!i++ ? "" : ", ") << "{" << pr.first << " : " << pr.second << "}";
  return o << "]";
}
template <template <class, class...> class S, class T, class... L>
ostream& operator<<(ostream& o, const S<T, L...>& v) {
  o << "[";
  int i = 0;
  for (const auto& e : v) o << (!i++ ? "" : ", ") << e;
  return o << "]";
}
template <class S, class T>
ostream& operator<<(ostream& o, const pair<S, T>& pr) {
  return o << "(" << pr.first << ", " << pr.second << ")";
}
ostream& operator<<(ostream& o, const string& s) {
  for (const char& c : s) o << c;
  return o;
}
template <class T>
using V = vector<T>;
template <class T>
using VV = V<V<T>>;
template <class T>
using VVV = VV<V<T>>;
using ll = long long;
using pii = pair<int, int>;
using vi = V<int>;
using vii = V<pii>;
using vvi = VV<int>;
using mii = map<int, int>;
using umii = unordered_map<int, int>;
using si = set<int>;
using usi = unordered_set<int>;
const int MX = 5e5 + 5;
int n, m, subTrSz[MX], height[MX], cntOdd[MX];
bool ans[MX];
string s;
vvi adj(MX), subTr(MX);
VV<pii> queries(MX);
V<map<char, int>> chars(MX);
void add(int node) {
  ++chars[height[node]][s[node - 1]];
  if (chars[height[node]][s[node - 1]] & 1)
    ++cntOdd[height[node]];
  else
    --cntOdd[height[node]];
}
void remove(int node) {
  --chars[height[node]][s[node - 1]];
  if (chars[height[node]][s[node - 1]] & 1)
    ++cntOdd[height[node]];
  else
    --cntOdd[height[node]];
}
void dfsSz(int node, int par, int dep) {
  height[node] = dep;
  subTrSz[node] = 1;
  for (auto& child : adj[node]) {
    if (child != par) {
      dfsSz(child, node, dep + 1);
      subTrSz[node] += subTrSz[child];
    }
  }
}
void dfs(int node, int par, bool keep) {
  int mx = -1, bigCh = -1;
  for (auto& child : adj[node])
    if (child != par && mx < subTrSz[child]) mx = subTrSz[child], bigCh = child;
  for (auto& child : adj[node])
    if (child != par && child != bigCh) dfs(child, node, 0);
  if (bigCh != -1) {
    dfs(bigCh, node, 1);
    swap(subTr[node], subTr[bigCh]);
  }
  subTr[node].push_back(node);
  add(node);
  for (auto& child : adj[node])
    if (child != par && child != bigCh)
      for (auto& x : subTr[child]) {
        add(x);
        subTr[node].push_back(x);
      }
  for (auto& pr : queries[node]) ans[pr.second] = (cntOdd[pr.first] <= 1);
  if (!keep)
    for (auto& x : subTr[node]) remove(x);
}
int main() {
  ios::sync_with_stdio(false);
  cout.precision(10);
  cin.tie(0);
  cin >> n >> m;
  int pi;
  for (int i = 2; i <= n; ++i) {
    cin >> pi;
    adj[i].push_back(pi);
    adj[pi].push_back(i);
  }
  cin >> s;
  dfsSz(1, -1, 1);
  int v, h;
  for (int i = 0; i < m; ++i) {
    cin >> v >> h;
    queries[v].push_back(make_pair(h, i));
  }
  dfs(1, -1, 0);
  for (int i = 0; i < m; ++i) cout << (ans[i] ? "Yes\n" : "No\n");
  return 0;
}
